changeBG=function() {
  var left, right, dzieci, h;
  
  // dodanie klasy short dla modułów z lewej krótszych niż 170px
  left = document.getElementById("jm-left");
  if(left){
    dzieci = left.childNodes;
    for(var i=0;i<dzieci.length;i++){
      if(/\bjm-inside-left\b/.test(dzieci[i].className)) {
        left=dzieci[i];
        break;
      }      
    }
    dzieci = left.childNodes;
    for(var i=0;i<dzieci.length;i++){
      if(/\bdjmodule.*\b/.test(dzieci[i].className)) {
        if(dzieci[i].offsetHeight){
          h=dzieci[i].offsetHeight;
        }
        else if(dzieci[i].style.pixelHeight){
          h=dzieci[i].style.pixelHeight;
        }
        if(h<100) {
          dzieci[i].className += " short";          
        }        
      }
    }
  }
  
  // dodanie klasy short dla modułów z prawej krótszych niż 182px
  right = document.getElementById("jm-right");
  if(right){
    dzieci = right.childNodes;
    for(var i=0;i<dzieci.length;i++){
      if(/\bjm-inside-right\b/.test(dzieci[i].className)) {
        right=dzieci[i];
        break;
      }      
    }
    
    dzieci = right.childNodes;
    for(var i=0;i<dzieci.length;i++){
      if(/\bdjmodule.*\b/.test(dzieci[i].className)) {
        if(dzieci[i].offsetHeight){
          h=dzieci[i].offsetHeight;
        }
        else if(dzieci[i].style.pixelHeight){
          h=dzieci[i].style.pixelHeight;
        }
        if(h<100) {
          dzieci[i].className += " short";          
        }        
      }
    }
  }
}


matchColumns=function(){
     var divs,contDivs,maxHeight,divHeight,d;
     // get all <div> elements in the document
     divs=document.getElementsByTagName('div');
     contDivs=[];
     // initialize maximum height value
     maxHeight=0;
     // iterate over all <div> elements in the document 
     for(var i=0;i<divs.length;i++){ 
          // make collection with <div> elements with class attribute 'container' 
          if(/\bbottom-inside\b/.test(divs[i].className)){ 
                d=divs[i]; 
                contDivs[contDivs.length]=d; 
                // determine height for <div> element 
                if(d.offsetHeight){ 
                     divHeight=d.offsetHeight; 					
                } 
                else if(d.style.pixelHeight){ 
                     divHeight=d.style.pixelHeight;					 
                } 
                // calculate maximum height 
                maxHeight=Math.max(maxHeight,divHeight); 
          } 
     }
     for(var i=0;i<contDivs.length;i++){ 
          contDivs[i].style.height=maxHeight + "px"; 
     }
}

window.onload=function(){
     if(document.getElementsByTagName){
          matchColumns();
          changeBG();
     }
}